In some of industrial vehicles, for example, a machine room is arranged behind a driver's cab and includes an engine room and a ventilation room which are separated by a dividing wall in a forward/rearward direction (a front direction of the driver's cab and its opposite direction). An engine is arranged in the engine room, and a radiator for the engine is arranged in the ventilation room.
In recent years, it has been proposed that to reduce NOx in an exhaust gas, such industrial vehicle includes an exhaust gas treatment device that executes a selective catalytic reduction (SCR) using urea water as a reducing agent. For example, as shown in FIGS. 5A and 5B, PTL 1 discloses an industrial vehicle 100 in which an exhaust gas treatment device 140 is arranged in an engine room 110 together with an engine 120.
Specifically, according to the industrial vehicle 100 disclosed in PTL 1, the exhaust gas treatment device 140 includes: a pretreatment unit 141 having a diesel particulate filter (DPF); and an SCR unit 142 that causes the urea water to react with the exhaust gas.
The pretreatment unit 141 is cylindrical, is arranged between the engine 120 and a dividing wall 130, and extends in a vehicle width direction. The SCR unit 142 is also cylindrical, is arranged above the pretreatment unit 141 and the engine 120, and extends in the vehicle width direction.
The pretreatment unit 141 includes an outlet 141a at a right side in the vehicle width direction, and the SCR unit 142 includes an inlet 142a at a left side in the vehicle width direction. The outlet 141a and the inlet 142a are connected to each other by a connecting pipe 143 extending in the vehicle width direction. Further, a urea water injection device 144 is attached to an end portion of the connecting pipe 143, the end portion being located at the right side in the vehicle width direction. The urea water injection device 144 injects the urea water into the exhaust gas in a direction along a center line of a linear portion of the connecting pipe 143, the linear portion extending in the vehicle width direction.
A radiator 170 for the engine is arranged in a ventilation room 150 that is separated from the engine room 110 by the dividing wall 130. Further, a urea water tank 160 storing the urea water is arranged under the ventilation room 150. Then, the urea water is guided from the urea water tank 160 to the urea water injection device 144 through a urea water pipe 161 penetrating the dividing wall 130. A urea water pump 162 is provided on a portion of the urea water pipe 161.